Key operated control means for radio receiving sets



April 28, 1936. E. R. STOEKLE 2,039,123

KEY OPERATED CONTROL MEANS FOR RADIO RECEIVING SETS Filed Novi 25, .1932 2 Sheets-Sheet 1 INVENTOR. WWW

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ATTORNEY) KEY OPERATED CONTROL MEANS FOR RADIO RECEIVING SETS Filed Nov. 25, 1932 2 Sheeis-Sheet 2 INVENTOR. M f m BY 6% 740M w,

WIEUM m A ATTORNEY} "UNITED STATES PATENT OFFICE aosa'izs KEY OPERATED CONTROL MEANS FOR RADIO RECEIVING SETS Erwin 1t. Stoekle, Milwaukee, Wis., aesignor to Central Radio Laboratories, Inc., Milwaukee, With, a corporation'of Wisconsin Application November 25, 1932, Serial No. 644,2

'6 Claims. (01. 201-55) This invention relates to an improvement in control devices for radio receiving sets and is especially applicable to that class of sets employed on automobiles.

5 The control device of the present invention is of the type which combines a volume control and v an "on and of! switch and the object of the present'invention is to provide a device of this character whereinthe switch is turned on and r "of! and the variable'resistance oi the volume control is adjusted by means of a key. The arrangement is such that the first turning movement of the key following its insertion brings about an actuation of the on and of! switch to throw-it to on" position and thereby energize the set. Continued turning movement of the key in the same direction cuts out resistance incorporated inthe volume control to increase the volume as desired. As the key is turned back toward its original position more resistance is cut into the circuit to thereby reduce the volume as may be desired.

Another object of the present invention is to provide a control device of this character which is simple and durable inits construction, closely and compactly organized, reliable and eflective in operation, easy and comparatively inexpensive to manufacture, and adapted to be conveniently installed on a suitable panel or bracket. other objects reside in certain novelfeatures of the construction, arrangement and combination of parts which will be hereinafter more fully described and particularly pointed out in the appended claims, reference being had to the accompanying drawings forming a part of this specification, and in which: Figure 1 is a view in elevation showing the volume control device and on and off" switch together with-a portion of a housing therefor, the 40 front plate of the housingand the parts carried thereby being omitted;

Figure 21s a similar view showing the front plate of the housing and the parts carried thereby, portions of the front plate being broken away '45 for the sake of illustration; 1

Figure 3 is a view in elevation showing the opposite side of the front plate 0! the housing from that shown in Figure 2, and also illustrating the parts disposed adjacent the inside face of 50 the front plate; 7 e e Figure 4 is a view in section taken on line 4-4 of Figure 1, parts being shown in elevation for the sake of simplicity in illustration;

Figure 5 is a similar view on line 5-5 of Fig- 55 are 1; 4

. of Figure 4; and

4 Figure Gisasectional view taken online 0-.

Figure 7 shows the housing in rear elevation. Referring to the drawings, the numeral I designates a housing which may be molded from in- 5' sulating material andhas a chamber or recess 2 7 formed within a projection 3 thereof and utilized to accommodate the -on" and "0!!" switch designated generally at S. The housing also.

provides a chamber ted generally at 4 in 10 which is mounted and housed the variable retact I3 is constructed of sheet metal and is 25 mounted for swinging movement on a stud l4 interconnected with the housing and having a portion projecting exteriorly thereof and riveted asat it to a binding post It. The interconnection of this movable contact I! with the stud i4 30 J is such as to allow free swinging movement of 'the movable contact. The portion of the movable contact which engages the fixed contact II hasopposifltly upwardly ilaring guiding lugs ll designed j'to insure overlapping engagement of the movable contact with the fixed contact II and with an abutment it formed as anintegral part of the housing. A portion ll of the movable contact is depressed or struck down to form a stop which limits the extent to which the movable con- 40 tact may overlap and engage the flgred contact II or the abutment II. This movable contact also constitutes one arm or link of a toggle, the other arm or link of which is designated at 2.. The toggle member or link 2| is also supported for swinging movement on the stud i 4 and may be held against displacement therefrom by means of a retaining clip 2L This toggle member I! is preferably constructed of insulating material and is connected to one leg of a toggle spring 22, the other'leg of this toggle spring 22 being interconnected. with a lug It struck fromthe movable contact member, .By shiftingthe toggle member 20 in one direction-or the other to a predetermined extent, the action of the spring may be reversed so that it will swing the movable contact member ii in one direction or the other with a snap action, the direction of swinging of the movable contact member depending upon the direction in which the toggle member 20 is swung. In cross section the toggle member 20 is generally U-shaped in that its body portion is provided with a pair of spaced parallel side flanges which extend outwardly toward the chamber 4.

The volume control device consists of a resistor suitably secured against a seat 3| provided therefor within the chamber 4. The resistor is of the type in which a suitable backing sheet or strip in the form of a split annulus is sprayed or otherwise coated with graphite. The ends of the graphite resistor are secured by rivets 32 passing through the housing I to binding posts 33 and 3t. Overlying the resistor is a metallic contact strip I5 of arcuate form, the ends of which are integral with the branches 3 of a supporting arm ll. The supporting arm 38 is secured in position upon seat 39 provided therefor, this securing being eifected by means of a rivet III which also electrically connects the supporting arm and consequently the metallic contact strip with a binding post ll disposed exteriorly of the housing, the rivet passing through the material of the housing as shown in Figure 4. The supporting arm ll tends to maintain the contact strip 35 spaced away from the resistor although the contact strip 38 is inherently resilient and may be displaced or flexed into contact with the resistor throughout its extent. It is obvious that the point to which the contact strip'li engages the resistor determines the extent to which the resistor is incorporated in the circuit.

Means is provided for flexing various portions of the contact strip 35 into engagement with the resistor and comprises a pressure button carried by a radial extension 46 of a disc H. The 7 disc 41 is connected to and rotated with the core 48 of a lock designated generally at L. A stop lug "is struck from the cover 5 and projects into a slot 50 formed in the disc 41, the lug I! being engageable with the ends oi the slot 5| to limit the rotation of the disc 41 and consequently of the pressure button in either direction. The lock L includes abushing Si in which the core I is rotatably supported. The inner end of this bushing is received in a central opening provided in the front plate 5 and it is suitably connected or fastened to the marginal edge oi such opening as indicated at 52. The bushing Si is externally threaded and its external threads are engaged by the internal threads of a sleeve 53 which completes the enclosure of the lock L and also provides a nut structure cooperable with the front plate in securingthe device in position on a panel or bracket. It is to be understood in this connection that the bushing 5| passes through an opening in such a panel or bracket and that the panel or bracket is clamped between the inner end of the sleeve 53 and the front plate 5 of the main housing.

The outer end of the sleeve 53 has inwardly directed annular flange 55 integral therewith and confining the edge of a disc 56 formed with a key slot 51. The flange 55 has a notch 58a alined with and forming a continuation of the key slot 51 in order that the key may be inserted and withdrawn in one position only wherein the on and oiP' switch has been turned to "011 position.

The core 48 is in the form of a cylindrical plug and has a reduced extension 48' projecting through the inner end of the bushing 5| and riveted to the disc 41. Forwardly the plug or core 48 has a longitudinal slot 58 designed to receive a portion of the key designated at 59. This plug 48 and the bushing 5i may be provided with conventional types of tumblers normally holding the plug against rotation but shifted by the key to release the plug for rotation when the key is inserted in the slot thereof. Such details of the locking mechanism are not shown as they are well known and widely used and per se form no part of this invention. In fact, in many instances, it may be desirable to omit them and merely rely on the configuration oi the keyhole rangement when the key is inserted and turned the initial turning movement moves the pin 60, and such movement of the pin 50 is transmitted through one of the flanges 25 to the toggle link 2| to swing this link 20 and cause it to reverse the action of the spring 22 and snap the switch to "on position,-that is to say, the movable contact I3 is shifted with a snap action from a position wherein it engages its abutment I! to a position wherein it engages the flxed contact ID of the switch. Upon further movement of the disc I! under the influence of the key the pin simply travels out of the space between the flanges 25 and such further turning movement merely shifts the pressure button 45 and varies the action of the volume control. However, upon return of the key to its original position the pin 50 reversely actuates the toggle link 2| to cause the switch to be snapped to the 05" position;

The key has a cross section or shape corresponding to the contour or formation of the slot 51 and it also has a notch 55 which, when the key is turned away from the notch 58, straddles a portion of the flange 55 thereby preventing withdrawal of the key except in the position wherein the switch is turned on.

While I have shown and described one construction as typical of the manner in which the invention may be embodied, it is to be understood that this construction has been selected merely for the purposes of illustration or example, and that various changes in the sire, shape and arrangement of the parts may be made without departing from the spirit of the invention or the scope of the subjoined claims.

The invention claimed is:

1. In combination with a volume control device having a housing and a variable resistance in said housing, a bushing connected to said housing and projecting therefrom, a slotted operating element for the variable resistance mounted in said bushing, a sleeve connected with said bushing and completing the enclosure of said operating element, said sleeve having an end wall provided with a keyhole slot and a key insertable through said keyhole slot and cooperable with said operating element whereby movement of the key throughout its entire range of rotation continuously regulates the action of the variable resistance.

2. The combination with a control means for radio receiving sets including a volume control device, an 'on and oil switch interlocked with said device to be actuated thereby, operating means for said device and a housing enclosing said device, switch and operating means, of a lock having a part interconnected with .said operating means for actuating the same, and a key cooperable with the lock whereby movement of the key throughout the entire range of rotation operates said lock and continuously regulates said volume control device, said lock having its enclosure connected to said housing and provided with means adjustably cooperable with the housing for supporting the control means.

3. The combination with a control means for radio receiving sets including a volume control device, an on and oil switch interlocked with said device to be actuated thereby, operating means for said device and a housing enclosing said device, switch and operating means, of a lock having a part interconnected with said operating a vice, an on" and off switch interlocked with said device to be actuated thereby, operating means for said device and a housing enclosing said device, switch and operating means, of a lock having a part interconnected with said operating means for actuating the same, a key cooperable with the lock whereby movement of the key throughout the entire range of rotation operates said lock and continuously regulates said volume control device, said lock having its enclosure consisting of a bushing connected to said housing and containing said movable part, and a sleeve threaded on said bushing and coacting' therewith to complete the enclosure and adjustably cooperable with the housing for supporting the control means in position, said bushing 7 having a disc at one end provided with a keyhole slot through which said key is inserted.

5. The combination with a control means for radio receiving sets including a volume control device, an on and off switch interlocked with said device to be actuated thereby, operating means for said device and a housing enclosing said device, switch and operating means, of a lockhaving a part interconnected with said operating means for actuating the same, a key cooperable with the lock whereby movement of the key throughout the entire range of rotation operates said lock and continuously regulates said volume control device; said lock having its enclosure consisting of a bushing connected to said housing and containing said movable part, and a sleeve threaded on said bushing and coacting therewith to complete the enclosure and adjustably cooperable with the housing for supporting the control means in position, said bushing having a disc at one end provided with a keyhole slot through which said key is inserted, there being cooperating means between said enclosure and said key to preclude removal of the key except when it is in such position that said switch is oii.

6. A control means for radio receiving sets comprising in combination, a revoliible rheostat volume control device an on and oil switch actuated by said device, operating means for said device having a slotted operating element, a housing enclosing said device, switch and operating means, said housing having a key hole slot in alinement with the slot of said element, and a key insertable through said key hole slot and adapted to fit in the slot of said operating element whereby rotation of said key eilfects the action of the switch and regulates the volume control device, said switch being in the of! posi tion and said key being removable when said slots are in alinement.

ERWIN R. STOEKLE. 

